The present invention relates to a generally elongated tampon for insertion into a mammalian body cavity. These tampons have smooth, apertured polymeric formed film covers to provide for smooth gentle insertion into and removal from a body cavity.
Catamenial tampons are used by women to absorb the flow of menstrual fluids to prevent leakage and staining of undergarments, and other clothing. Therefore, it is desirable for tampons to demonstrate good absorbency and to be able to absorb fluid quickly. Unfortunately, tampons are not without disadvantages and inconveniences. For example, tampons may unexpectedly leak if they do not expand quickly enough or fully enough to fill the vaginal canal. Tampons are also sometimes difficult or uncomfortable to insert into or remove from the vaginal canal. These insertion and removal difficulties may be especially apparent when the menstrual flow is light.
There have been many attempts to remedy these problems by altering the absorbent material or the outer cover of the tampon. Greener et al., U.S. Pat. No. 2,710,007, and Burgeni, U.S. Pat. No. 3,340,874, are examples of the use of low density material in portions of a tampon to promote rapid fluid absorption.
Gellert, U.S. Pat. No. 4,475,911, describes a tampon made up of an unbonded array of nonabsorbent, hydrophilic, resilient fibers completely enclosed within a porous overwrap of apertured formed film.
Thompson, U.S. Pat. No. 3,929,135, describes a topsheet useful in disposable absorptive devices, including catamenial tampons. The topsheet is an apertured formed film having tapered capillaries. The Examples in this reference describe a topsheet having a top surface which is more than about 90% open area.
Lloyd et al., U.S. Pat. No. 5,374,258, describes a tampon with a cover comprising lengthwise ribs. The ribs on the cover are parallel to the tampon""s axis and are separated from one another by multiple transverse ribs. Howarth, U.S. Pat. No. 5,403,300, describes a tampon with a polymer net outer cover. The net comprises two intersecting sets of parallel ribs which are aligned obliquely with respect to the main axis of the tampon and to each other. The orientation of the ribs allegedly aids in the smooth insertion and removal of the tampon.
Commonly assigned, copending patent application to Foley et al., U.S. patent application Ser. No. 08/789,747 (also published as EP 685 215) describes a tampon which demonstrates low capillary suction pressure on the vaginal epithelium. The contents of this application are hereby incorporated herein by reference.
It is an object of this invention to provide a novel tampon with good absorbency and leakage protection, ease of insertion into and removal from a body cavity, and a relatively clean dry surface after use.
The tampons of this invention provide good absorbency and protection from leakage while providing a smooth surface for easy, gentle insertion into and removal from the vaginal canal. They accomplish this by providing a generally elongated absorbent core made from absorbent materials, and an outer cover made from an apertured formed film. The apertured polymeric formed film comprises a land region having a multiplicity of openings therein. Each of these openings is defined by a first aperture and sidewalls extending in a uniform direction from the first aperture. The side walls terminate in a second aperture. The open area formed cumulatively by the second apertures comprises less than about 35% of the surface area of the apertured polymeric formed film. The outer cover is oriented on the tampon such that the second apertures are adjacent the absorbent core.
The apertured formed film provides a generally smooth land area on the outermost surface of the tampon for gentle, nondrying passage along the vaginal walls. The apertures in the film allow fluid to pass through the cover and into the absorbent core, where the fluid is held to prevent leakage.
The tampon of the invention may be made by forming a generally elongated blank of absorbent material, attaching a length of apertured polymeric formed film so that it covers at least the generally elongated surface of the blank, and then compressing the covered blank to form a tampon. A withdrawal cord or string may be attached to the blank or the covered blank to aid a user in withdrawing the tampon from a body cavity after use.